The flute is a member of
the woodwind family (see Figure 1). A player
blows air across the hole in the side of the head joint, which causes air
flow patterns at the edge of the lip plate to alternate rapidly.
The alternation causes the air in the tube to resonate. Waves reflect
back and forth in the column of air, creating the tone of the flute.
The lowest note can be played when all the tone holes are closed and the
column is at its maximum length. Opening the tone holes starting
at the open end effectively shortens the column.
The sound of a musical
instrument consists of a fundamental frequency plus other higher frequencies
(overtones) that form the harmonic series. The overtones are multiples
of the fundamental frequency. If f is the fundamental, the overtones
are 2f, 3f, 4f, 5f, etc. Each instrument has a unique sound depending
on how much of the other frequencies are present in each note. Although
people have different perceptions of a good sound, a full sound is generally
one that has a lot of overtones. A listener can hear a difference
between sounds with and without overtones. A sound is sometimes called
tinny if it has a lot of the higher overtones, and it is called mellow
if it only consists of the fundamental frequency. In order to characterize
the frequency spectrum of the flute, I took sound samples based on different
parameters of several flutes. In the power spectrum of each sample,
I expected to see spikes at the fundamental frequency and at each overtone.
The main focus of this project was A at 440 Hz, but I also took samples
of other octaves of A and also of B. Table 1 shows the first 7 overtones
of the harmonic series of A at 440 Hz and the corresponding notes for each
overtone.
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My goal was to determine if there were patterns in the power spectrums, possibly depending on the flute, the player, or both.
Abstract
Introduction
Experimental Setup
Results
Discussion
Conclusions
References